Process of making colored sheet glass



Dec. 30, 1941. J ox 2,268,247

PROCESS OF MAKING COLORED SHEET GLASS Fil ed Dec. 15, '1937 2 Sheets-Sheet l .INVENTOR.

Dec. 30, 1941. r J. H. FOX 2,268,247.

PROCESS OF MAKING COLORED s HEET GLASS 7 Filed Dec. 15, 1957 2 sheets-shed 2 INVENmR.

RNEYS.

s PATENT oFF-lcs um'rso STATE amass PROCESS OF MAKING COLORED SHEET GLASS John H. l 'ox, Pi

Pm, assignor to Pittsburgh Plate Glass Company, Allegheny County. Pa., a corporation of Pennsylvania Application December 15, 1937, Serial N0. 179,815

i The invention relates to a process whereby a colored glass may be made in an ordinary sheet glass machine}, such as. that of Slinglulf or Colburn, by simple additions thereto permitting the it follows a path somewhat as indicated at it and becomes incorporated into the glass sheet I providing the desired color in such sheet. This color is mixed through the body of the sheet. and

making of ordinary colorless sheet glam when the by regulating the flow ct material from the hopcolor supply means are discontinued. It has per, the degree of color in the sheet may he been proposed heretofore to accomplish this revaried to suit requirements. The hopper is illled suit by feeding either colored glass in molten or with a colored glass by ladling from a small tank powdered formonto the surface of the bath adof colored glass or by a supply from pots of coljacent the line of draw of the sheet, so that a ored glass which are heated in a'sepflrate kiln. colored layer is supplied to one side of the sheet, The hopper is provided with a suitable cover the body of thesheet being or clear glass. This l'l which is movedinto and out of place from two layer glass, known as flashed glass, has a an overhead crane bymeans of a chain it eoncoating which is relatively'thin and transparent, nected to brackets n. This cover prevents the tending in some cases to separate from the body glass from cooling toov rapidly and in order to of clear glass, if the two glasses are not exactly fltted" to each other. The present method has for its objects the provision of a process which will give a sheet colored throughout its thickness, as opposed to the flashed" or two layer glass, and which shows, with transmitted light, denser color and less transparency. Two forms of the apparatus are shown in the accompany ing drawings, wherein: V

Figure 1 is a vertical section through the apparatus. Fig. 2 is an isometric view of the hopper which contains the colored glass. Fig. 3 is a section through a modification. And Fig. 4 is an isometric view of a modified form of hopper.

Referring to the drawings, I is a melting tank and 6 is a drawing extension or forehearth from which a glass sheet I is drawn continuously. The drawing is accomplished by a Fourcault leer well known in the art and comprising a casing I and a series. of pairs of drawing rolls 8 which grip the sides of the sheet'and draw it continuously through the leer to the upper end where it is cut in sections; .The usual skim bar II is employed between the melting tank and its forehearth and a pair or L-blocks ii are supported on either side of the line of draw of the sheet, as is common in the art. A draw bar l2 extends transversely of the tank beneath the line of draw and serves to position the line of draw or glass below the surface thereof through the line of openings I! (Fig. 2). These openings are intermediate the level of the upper side of the draw a bar andthe surface of the glass, and when the give still further heat, burners may be applied through suitable openings II in the cover. The cover also carries the gate 2| for controlling the flow of glass through the openings ll. This gate dovetail slots 24 (Fig. 2) in the upper end of the gate. Additional heating means for the hopper may be provided in the form of resistance elements 25 embedded in the walls of the hopper,

such elements being connected to a suitable source ofcurrent (not shown). An additional heating effect is also secured by means of the electrodes 20,28 which engage the glass bath and by the lead 21 connected to the gate. The leads 2'! and II are connected to a'suitable source of current supply and the ilow of current from the gate to the electrodes" heats the glass flowing through the openings II and the glass adjacent thereto in the bath. This obviates any danger of the glass freezing up in the openings II and serves as an additional means for regulat- 40 ing the flow.

Fig. 3 illustrates a modification in which the hopper 211s located on the side of the line of.

draw remote from the melting tankinstead of being located on the side thereof adjacent to the the sheet and give a somewhat cooler layer of melting tank as in thevFig. 1 construction. The glass from which to draw, in order to increase details of construction of the hopper are the the drawing speed. v same asheretofore described and require no fur- Extending transversely of the tank isa hopther description being similarly numbered. The per it which carries a body of molten colored electrical heating connections for the bath and glass H, which glass is fed into the body of clear gate are dispensed with in this particular construction. I

Fig. 4 illustrates a hopper 3| which diifers from that of Fig. 2 inthat no provision is made for electrical heating and the outlet at the lower 7 glass fflcws into the forehearth fromthe hopper, end is in the form of a slot ll which takes the used with a gate slmllar to that 1 and 2.

What 1 claim is:

A method or making a glass sheet, which consists in drawing a sheet vertically from the surface or a molten'bath of clear glass above a draw shown in Figs.

aaeaa'u place of the series 0! openings Ii of the first WW v of construction. This hopper is designed to he JOHN H. FOX. 

